SewerOwner

Pipe bursting

Pulling a new pipe along the existing route while displacing the old one.

What this page cannot establish

  • SewerOwner cannot establish whether pipe bursting is appropriate for your property
  • this approach cannot establish that the route is suitable without site-specific assessment
  • this approach cannot establish the position of other buried services
  • this approach cannot establish that this method is preferable to any other for a given property

What it attempts to do

Replace the pipe along its existing route by drawing new pipe through while the existing pipe is displaced outward, using pits rather than a full-length trench.

When contractors may discuss it

These are circumstances in which the approach comes up, not a checklist that makes it correct. There is no situation in which one method is universally right.

  • when replacement rather than repair is being considered
  • when surface disturbance along the route is a significant concern
  • where the route and site conditions allow the equipment to work

What has to be known before applicability can be judged

If a proposal for this work is priced without these, it is priced against assumptions. That is not necessarily wrong — but the assumptions should be written down.

  • the route, length, and approximate depth
  • what other buried services run near the route
  • the ground conditions along the route
  • where access pits can be placed
  • whether any branch connections enter the run

Access and site considerations

  • requires access pits, typically at each end
  • requires equipment access to the pits
  • nearby buried services are a significant planning consideration
  • surfaces at the pit locations are disturbed

What to clarify in a proposal for this work

These are the details that most often differ between two proposals for what sounds like the same job.

  • where the access pits will be located and what surfaces they affect
  • the replaced length, stated as start and end points
  • assumptions about ground conditions and obstructions
  • how any branch connections are reinstated, if applicable
  • what happens if the pull cannot be completed
  • restoration for each affected surface

What to keep afterwards

  • photographs of the pits before backfill
  • the permit and inspection record
  • post-work footage
  • warranty terms as written

Alternatives worth asking about

Asking why one approach is proposed rather than another is a reasonable question, and the answer tells you what the contractor believes about your line.

Traditional excavation

Digging along the line to expose and replace pipe directly.

Expose the line so that pipe can be removed and replaced, and so that what is uncovered can be observed directly.

Cannot establish: the condition of any section outside the excavation; that no further conditions exist elsewhere; that the new installation will perform for any stated period.

Cured-in-place lining

Installing a liner inside the existing pipe that hardens in place.

Create a new pipe wall inside the existing line, using the existing pipe as the host, without excavating the full route.

Cannot establish: that lining is appropriate for a given line without inspection; the condition of the ground around the host pipe; that the host pipe’s surroundings are unaffected; that this method is preferable to any other for a given property.

Rerouting

Installing the line along a different path rather than the existing one.

Establish a new route for the line where the existing route presents difficulties that a same-route method would not resolve.

Cannot establish: that a new route is permissible without checking; that the new route avoids all obstructions.

What would change the answer

  • the route, length, and approximate depth
  • what other buried services run near the route
  • the ground conditions along the route
  • where access pits can be placed
  • whether any branch connections enter the run

What to do next

Bursting still disturbs surfaces at the pits, and pit location is frequently under-specified.

Find out where the pits go and what they affect

If your situation is different

Related, and why